Spain earthquake: How a small quake caused so much damage [VIDEO]

Spain earthquake: The quakes that struck Spain Wednesday were seismically mild, but they occurred close to the surface, geologists say.

By
Andrea Mustain, OurAmazingPlanet Staff Writer /
May 12, 2011

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A building lies in ruins in Lorca, after a rare earthquake rocked the town in southeastern Spain, causing houses to collapse, damaging historic churches and public buildings and killing at least six people Wednesday.

Francisco Bonilla/Reuters

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The two earthquakes in Spain Wedesday (May 11) that killed nine people and caused significant damage struck an area with a tame seismic history. Their shallow point of origin contributed to the deaths and destruction.

An estimated 10,000 people have been told not to return to their homes.

The quakes, which occurred along a yet-unidentified fault, were shallow, rupturing just over a half-mile (1 kilometer) below ground, said John Bellini, a geophysicist with U.S. Geological Survey.

"Earthquakes close to the surface cause the most of damage no matter what type of fault it is," Bellini told OurAmazingPlanet.

Footage of the quake broadcast on a Spanish news channel shows a church tower falling to rubble and bricks crashing onto cars on the street below.

The earthquakes appear to have wrought outsize destruction for their relatively low magnitude, a fact that could be due to a prevalence of older buildings in the region.

Bellini said an earthquake of a magnitude 6.5 in Tokyo, a city with strict earthquake codes, built to withstand powerful shaking, would likely cause very little damage. But in a place like this area of Spain, where earthquakes are less anticipated, buildings are less likely to be earthquake-resistant.